• Title/Summary/Keyword: effect of fluidity

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Effect of Pine Needle Extract (PNE) on Physilolgical Activity of SD Rats III. Feeding Effect of PNE on Fluidity and Neurotransmitter-Related Enztmes in Brain Membranes of SD Rats (흰쥐의 생리활성에 미치는 송엽(松葉) 추출물(PNE)의 영향 III. 뇌세포막의 유동성 및 신경전달관련 효소의 활성에 미치는 PNE의 투여효과)

  • Choi, Jin-Ho;Kim, Jung-Hwa;Kim, Dong-Woo;Hwang, Chan-Ho;Kim, Dae-Ik;Lee, Jong-Soo
    • Journal of Life Science
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    • v.8 no.2
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    • pp.167-172
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    • 1998
  • To investigate the effect of pine needle extract (PNE) on membrane fluidirt and neurotransmiter-related enzymes in brain of Spragu-Dawley(SD), male SD rats were fed basic diets (control group), and experimantal diets (PNE group)with 0.5% and 0.1% fo PNE for 6 weeks. pine (pinus tabulaeformis C$_{ARR}$ is one of the popular plant drugs which has used as a medicine in Asia. Cholesterol levels in brain mitochondria of 0.5%-PNE and 0.1%-PNDE groups were significantly decreased in 15% and 25%, respectively, compared with control group, but cholesterol levels in brain microsomes of these PNE groups howed almost no change compared with control group. Lipofuscin accumulations in brain membranes of 0.5%-PNE and 0.1%-PNE groups were sgnificantly inhibited in 18% and 21%, respectively, compared with control group. Brain memberance fluidity was also activated in 50% and 100% by the administration of 0.5%-PNE and 0.1%-PNE. higher acetylcholinesterase(15% and25%) and lower monoamine oxidase B (25% and 15%0 activities were effectively modulated by the administration of 0.5%-PNE and 0.1%-PNDE. These results suggest that more beneficial effects such as inhibition of cholesterol and lipofuscin, increase of membrane fluidity, higher acetylcholinesterase and lower monoamone oxidase activities in brain membranes of SD rats may be effectively modulated by administration of pine needle extract (PNE).

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The Effect of the Membrane Fluidity of Bellflower(Platycodon grandiflorum A.) Fractions on Liposomal Phospholipid Membranes (도라지 분획성분이 인지질막 Liposome의 유동성에 미치는 영향)

  • 배송자;강보영
    • Journal of Life Science
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    • v.12 no.2
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    • pp.121-128
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    • 2002
  • The object of this study was to investigate the effect of membrane fluidity of bellflower(Platycodon grandiflorum A. DC, ; PG) fractions in phosphatidylcholine(PC) liposomes, measured with high-sensitivity differential scanning calorimetry(DSC). We used dipalmitoylphosphatidylcholine(DPPC) bilayers which slake most stable liposomes among the other phosphatidylcholine. The sample PG was extracted and fractionated to five different types : butanol(PGMB), ethylacetate(PGMEA), ethylether(PGMEE), hexane (PGMH) and methanol(PGMM). Among five different solvent fractions, the PGMEE, PGMEA, PGMH and PGMM fractions markedly affected the thermotropic properties of DPPC liposomes, broadened and shifted the thermograms, and reduced the cooperative unit. It might be said that the incorporation of PGMEE, PGMEA and PGMH in DPPC liposomes were located in the hydrophobic core of DPPC bilayers and, PGMM and PGMB in the hydrophilic core of DPPC bilayers. These results suggest that certain substances in the PGMEE, PGMEA and PGMH fractions might have biologically significant effect on the membrane fluidity.

Solanum Nigrum Polysaccharide (SNL) Extract Effects in Transplanted Tumor-bearing Mice - Erythrocyte Membrane Fluidity and Blocking of Functions

  • Yuan, Hong-Liang;Liu, Xiao-Lei;Liu, Ying-Jie
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.23
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    • pp.10469-10473
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    • 2015
  • Background: Solanum nigrum L. has been used in traditional Chinese medicine because of its diuretic and antipyretic effects. The present research concerned effects of crude polysaccharides isolated from Solanum nigrum L. on erythrocyte membranes of tumor-bearing $S_{180}$ and $H_{22}$ in mice. Materials and Methods: Fluorescence-labeled red blood cell membranes were used with DPH fluorescence spectrophotometry to examine erythrocyte membrane fluidity, and colorimetry to determine degree of erythrocyte surface membrane blocking. Extent of reaction by tumor-bearing mice with the enzyme erythrocyte membrane bubble shadow detection of red cell membrane variation in the degree of closure before and after administration. Results: Solanum nigrum polysaccharide could significantly improve the $S_{180}$ and $H_{22}$ tumor-bearing mice erythrocyte membrane fluidity, compared with the control group, the difference was significant (p<0.01), SNL can significantly improve the red blood cell membrane and then $S_{180}$ tumor-bearing mice sealing ability, compared with the negative control group, the difference was significant(p<0.05, p<0.01). $H_{22}$ tumor-bearing mice can increase red cell membrane and then sealing ability, the difference was significant (p<0.05). Solanum nigrum polysaccharide degree of fluidity and blocking two transplanted tumors in mice restored the ability to raise the red cell membrane has a significant effect. Conclusions: Solanum nigrum L.-type mice transplanted tumor can affect the red blood cell membrane fluidity and re-closed, through the red cell membrane of red blood cells to enhance the immune function of the possibility of erythrocyte immunity against tumor formation garland provide experimental basis.

Effect of Waste Marble Powder on the Fundamental Properties of High Fluidity Concrete (폐 대리석 분말을 혼입한 고유동 콘크리트의 기초적 특성에 대한 실험적 연구)

  • Lee, Yong-Moo;Shin, Sang-Yeop;Kim, Young-Su
    • Journal of the Korea Institute of Building Construction
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    • v.15 no.2
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    • pp.153-160
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    • 2015
  • The marble powder is a by-product that can be freely collected during the manufacturing process of marble, such as sawing, shaping, and polishing. Disposal of this waste powder is one of the environmental problems worldwide today. Therefore, this study investigated to solve this problem by consuming the waste marble powder in high fluidity concrete, as a pore filler. For this purpose, the waste marble powder was used as a binder replacing 5%, 10%, 15%, and 20% of cement in high fluidity concrete. After mixing, slump flow test, time-to-reach the slump flow of 500mm test, O-lot test and U-box test were conducted with fresh concrete. For the hardened concrete, compressive strength was determined at the age of 28 days. According to the test results, the workability of high fluidity concrete increased with the powder of 15% replacement, and the compressive strength of high fluidity concrete also increased with the same amount of powder.

Evaluation of Mixing Conditions for the Production of Optimized High Flowing Concrete

  • Kim, Sang-Chel
    • KCI Concrete Journal
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    • v.11 no.3
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    • pp.79-88
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    • 1999
  • Most difficulties of inducing high fluidity on the concrete mixing design with a strength range of 210 to 240kg/$\textrm{cm}^2$ result from the segregation of aggregates due to the shortage of cementitious binders. To solve the problem, this study concentrated on finding the optimized amount of binder material which does not affect the concrete strength and is also economical. Also there were studies on the use of intermediate sized aggregates to avoid the gap-grading between coarse and fine aggregates so that the material segregation in high flowing concrete was and minimalized the fluidity and penetration capacity of the reinforcing bars was enhanced. Throughout the parametric study with respect to water/binder ratio. superplasticizer. replaceable mineral admixture, the size of coarse aggregate and mixing methods, the effect of each constituent on the characteristics of high flowing concrete could be observed. As a result or partially using stone powder or an intermediate class of aggregate (max. diameter 13mm) . it was fund that the fluidity of concrete significantly increased without material segregation and any change of compressive strengths. It was also proved in this study that proper mixing time and speed are significant factors influence the performence of high flowing concrete.

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Observation of nano powders and fly ash usage effects on the fluidity features of grouts

  • Celik, Fatih;Yildiz, Oguzhan;Bozkir, Samet M.
    • Advances in nano research
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    • v.13 no.1
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    • pp.13-28
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    • 2022
  • The pumpability of the grouts is significant issue in concept of the rheological and workability properties during penetrating to voids and cracks. To improve the fluidity features of the grout mixes, the usage of Colloidal Nano Particular Powders (CNPPs) with mineral additives such as fly ash (FA) can contribute. Therefore, the main purpose of this study can be explained as investigating the usage effects of four types of Colloidal Nano Particular Powders (n-TiO2, n-ZnO, n-Al2O3 and n-SiO2) as nano additives on the rheological, workability and bleeding properties of cement-based grout incorporated with fly as. Test results showed that the usage of FA in the grout samples positively contribute to increase on the fluidity of the grout samples as expected. The dilatant behavior was observed from the results for all mixes. Observing the effect of nano-sized additives in such cement-based grout mixtures with high fluidity has presented remarkable effects in this study.

Influence of Unit Water and Viscosity Agents Contents on the Bleeding of Concrete (단위수량 및 증점제량이 콘크리트의 블리딩에 미치는 영향)

  • 김은호;심보길;황인성;전충근;한천구
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.11a
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    • pp.232-328
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    • 2001
  • This paper investigates the influences of water content and viscosity agent on the bleeding of concrete. According to test results, fluidity shows decline tendency as water content decreases, and dosage of viscosity agent increases. PEO viscosity agent does not affect the air contents while, MC viscosity agent causes air loss. As for bleeding, bleeding decreases with decrease of water content. As dosage of viscosity agent increase, bleeding decreases, regardless of viscosity kinds. It is thought that viscosity agents have the favorable effect of reducing bleeding, if fluidity and air loss are improved.

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An Experimental Study on the Fluidity Performance and Engineering Properties of Crushed Stone Concrete Using Superplasticizers (고성능 감수제를 사용한 쇄석 콘크리트의 유동화 성능 및 공학적 특성에 관한 연구)

  • 송하영;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • 1990.04a
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    • pp.16-19
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    • 1990
  • The effect of superplasticizers on the fluidity performance in fresh concrete and physical properties in hardened concrete have been analyzed and investigated under mix proportions of water cement ratio of 0.4, 0.6, crushed stone aggregates, and addition rates of superplasticizers of 0.0, 0.5, 1.0 and 1.5 in the practical range. It is the aim of this study to provide the fundamental data on the workability improvement and engineering properties of crushed stone concrete using superplasticizers comparing with conventional concrete for the practical use and research data accumulation of superplastized concrete.

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Effects of Microstructure Morphology on Fluid Flow Characteristics of A356 Commercial Alloy in Semi-Solid Slurry (반고상 A356 합금 슬러리의 미세조직에 따른 유동특성에 관한 연구)

  • Kim, Jae-Min;Lee, Seung-Hoon;Hong, C.P.
    • Journal of Korea Foundry Society
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    • v.25 no.6
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    • pp.240-248
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    • 2005
  • The rheocasting characteristics are strongly influenced by the microstructural morphology such as particle size, form factor and contiguity. In this study, the effect of structural morphology on fluid flow characteristics of A356 semi-solid alloy was investigated with a vacuum suction fluidity test. Semi-solid metal slurry was made by the mechanical stirring, the liquidus casting, and H-NCM to be analysed. H-NCM could obtain uniform and fine globular microstructures of 0.9 form factor and 55 ${\mu}m$ particle size. Inoculation was found to be effective for reducing particle size, however, for H-NCM it should be avoided due to the cause of increasing contiguity. The fluidity test indicated that the non-stirring method had higher fluidity and smaller liquid segregation in the same solid faction of 0.4 than the stirring method, for smaller particle size and higher form factor. It was observed that liquid segregation decreased as the particle size is smaller and form factor is higher. The results of die-casting experiment were a good agreement with those of fluidity test.

Rheological properties According to the Pigment Particle size of Ink (안료입자크기에 따른 잉크의 레올로지 성질의 변화)

  • Park, Jeung-Min;Kim, Sung-Bin;Kim, Jong-Won
    • Journal of the Korean Graphic Arts Communication Society
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    • v.21 no.2
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    • pp.75-87
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    • 2003
  • Printing inks are mainly composed of pigment and vehicles. Among these components, the Vehicle affect the rheologic property of the ink the most but pigment content of characteristic also after to the fluidity property not less than the vehicle. In the study, It is tested effect to the ink fluidity and structure recovery according to change the pigment particle size. The ink fluidity have been observed by using rheometer at the various conditions and it has been tested to observe what the ink fluidity has different means. In result We have found that the viscosity value of the low shear rate range has relatively higher value with decreasing the pigment particle size in the ink. Also, it has been found that when the pigment particle size decreases, the yield stress gradually increase. In the case of ink's structure recovery, when the pigment particle size decreases in the ink, the less changing shear rate, and it takes less time to recover.

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